Knife sharpener



FIG. 1 is a front perspective view of a knife sharpener embodying my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a rear side elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a top plan view thereof;

FIG. 8 is a front elevational view of a modified embodiment of FIGS. 1-7;

FIG. 9 is a right side elevational view of the embodiment of FIG. 8;

FIG. 10 is a rear side elevational view of the embodiment of FIG. 8;

FIG. 11 is a left side elevational view of the embodiment of FIG. 8;

FIG. 12 is a bottom plan view of the embodiment of FIG. 8;

FIG. 13 is a top plan view of the embodiment of FIG. 8; 

The ornamental design for knife sharpener, as shown and described. 